Improved performance of Backlog loading, Improved init performance significantly.

...main/java/de/kuschku/libquassel/client/BufferManager.java

app/src/main/java/de/kuschku/libquassel/client/Client.java

...n/java/de/kuschku/libquassel/events/BacklogInitEvent.java

.../java/de/kuschku/libquassel/localtypes/BacklogFilter.java

...schku/libquassel/syncables/types/impl/BacklogManager.java

...hku/libquassel/syncables/types/impl/BufferViewConfig.java

...e/kuschku/libquassel/syncables/types/impl/IrcChannel.java

...a/de/kuschku/libquassel/syncables/types/impl/Network.java

...ibquassel/syncables/types/interfaces/QBacklogManager.java

...ku/libquassel/syncables/types/interfaces/QIrcChannel.java

...java/de/kuschku/quasseldroid_ng/ui/chat/ChatActivity.java

...a/de/kuschku/quasseldroid_ng/ui/chat/NickListWrapper.java